Extrusion apparatus



E. A. ANDREW EXTRUSION APPARATUS Filed March 28, 1955 Jan. 1, 1957 FIG].

Irma/Keys.

FICA,

[#65449 Illa-r A EXTRUSION APPARATUS Eugene A. Andrew, St. Louis, Mo.,assignor 'to' Olin Mathieson Chemical Corporation, East Alton, Ill., a

corporation of Virginia Application March 28, 1955, Serial No. 496,968

1 Claim. (Cl. 18-12) This invention relates'generally to the treatmentof plastics and particularly to an apparatus for extruding a body oflacquer or the like and simultaneously cutting the extrusions intodiscrete particles. 4

In my copending application Serial No. 470,412, filed November 22, 1954,and the copending application of myself and Ralph L. Cook, Serial No.460,014, filed October 4, 1954, there is disclosed an apparatusfor-extruding lacquer or the like, and concomitantly severing theextruded streams into discrete articles. As disclosed in thoseapplications, the lacquer to be extruded is introduced under pressureinto a chamber from which the lacquer escapes through a plurality ofextrusion orifices in a flat plate; and cutter blades are mounted forrotation so that each passes successively across the series of orificesand severs the increment of lacquer which has been extruded through eachorifice (since a blade last passed that orifice) from the body oflacquer within the orifice and within the pressure chamber. The cutteris mounted for rotation about an axis disposed centrally of the orificeplate, and consequently, each blade of the cutter passes successivelyover all of the orifices in that plate during each revolution of thecutter. In such an arrangement, however, the lineal velocity of thecutter blades increase from the center of rotation outwardly; Thus whena cutter blade moves through an extrusion located toward the outer edgeof the orifice plate, it is moving at a higher velocity than when itmoves through a similar extrusion from an orifice located nearer thecenter of the orifice plate. xThis uneven velocity of cutting results,to a small extent, 'in uneven or ragged cutting of the extrusions.Furthermore, since the cutter blades have width, each orifice is coveredby the blade in passing so that where the blade is of uniform width fromend to end, the orifices near the center are covered by the blade for alonger increment of time, during each pass, than are the orificesfarther from the center; and this results in some unevenness of thelength of the extrusion severed. Moreover, with an arrangement of thekind disclosed in said applications Where the cutter blades project froma central hub, a good portion of the orifice plate near its center isnot useable because it is covered by the hub; and this restricts thenumber of blades which may be used because the space between blades mustbe sufiicient to enable an extrusion of the desired length to take placebetween passes of successive blades. For example, with an orifice platefour inches in diameter, the maximum practical number of cutter bladesis four.

The object of the invention generally stated is to provide an apparatusfor extruding and severing lacquer and the like in which the rate ofproduction of severed bodies is higher, and the product more uniformthan with the apparatus disclosed in the aforesaid applications.

A more specific object of the invention is to provide a device for thepurpose described wherein the velocity of cutting at all orifices isconstant.

A further specific object of the invention is to pro- Wide a device forthe purpose described wherein the num- 2,775,788 Patented Jan. 1, 1957ber of cutting'edges may be increased over that which is practical withdevices of the type disclosed in the aforesaid application.

Generally stated, these objects are accomplished by extruding thelacquer or the like through a multiplicity of orifices in a cylindricalwall, and concurrently moving a series of blades about said wall inshearing relationship with the edges of the multiplicity of orifices.For example, the chamber into which the lacquer is introduced underpressure and from which the lacquer is extruded,

may be provided with an exterior cylindrical wall having a multiplicityof orifices therein. A series of cutter blades, each extending in thegeneral axial. direction of said cylinder, is mounted for rotationrelative to the cylinder and coaxial therewith, so that the blades rideupon the surface of the cylinder, and, in each revolution, each bladesuccessively passes all of the orifices at the same lineal velocity andeach blade obstructs the passage of lacquer through each orifice for thesame increment of time. Thus a four inch diameter cylinder may beequipped with asmany as twelve blades.

One embodiment of the invention is illustrated in the accompanyingdrawing in which:

Figure 1 is a longitudinal sectional view of such an apparatus;

Figure 2 is a sectional view taken along line 2-2 of Figure 1;

Figure 3 is a view in side elevation of the cutter element shown inFigure l;

Figure 4 is a view in side elevation of the cylindrical extrusionchamber shown in Figure 1; and

Figure 5 is a sectional view taken along line 5-5 of Figure 3.

In the form shown in the drawing, the apparatus comprises an enclosingvessel 1, preferably of cylindrical shape, having an intake port 2 forsuspending liquor, and an outlet port 3 for discharging the suspensionof lacquer particles in suspending liquor. The vessel 1 is mounted upona base 4 having a central inlet 5 for receiving lacquer under pressurefrom an external source, not shown. The vessel 1 is also provided with acap 6 having a central hub 7 which latter provides a bearing and sealfor a shaft 8 driven by an external source of power, not shown. V

A chamber element 9, having an exterior cylindrical surface and amounting flange 10, is mounted upon base 4 and the cylindrical wall ofvessel 1 is secured in sealed relationship to flange 10, as shown at 11,so that a substantial space is provided between the exterior of chamber9 and the interior surface of vessel 1. With the arrangement as shown,the lacquer under pressure, introduced through inlet 5, occupies theinterior of chamber 9, and in order to extrude the lacquer, thecylindrical wall of chamber 9 is provided with a multiplicity oforifices 12. The pressure on the lacquer within chamber 9 forces thelacquer out through orifices 12. The several orifices 12 have a diameterchosen in accordance with the size of the streams it is desired toextrude through them. Preferably all of the orifices in a given chamber9 are of the same size.

On the end of shaft 8 within vessel 1, there is mounted a cutter element13 which, in the form shown in the drawing, is an open-ended cylinderhaving an internal diameter such as to provide a running fit with theexterior cylindrical surface of chamber 9. The cylindrical wall ofcutter element 13 is cut away by the removal of strips of materialtherefrom, as shown at 14, in order to provide a series of spaced blades15 which are integral with circular bands 16 at the opposite endsthereof. In the form shown, the several blades 15 extend in a generalspiral direction about the cylinder. The spiraling of the blades has theadvantage that when the cutter clement isibtatedindir'ection shown bythe arrow on "Figure 3fthemovement" 'of' 'bladesdefl'ects' the sev'eredlacquer particles in an upward direction which is concurrent with themovement of the suspending liquor 'tfiioifgh the vessel 1. f'ljhespitting-Thames fiirtli'er aidtia'gtaht the armada "thereby is" a a awia"eat as distinguished from a chopping cut, and'tlius lfiitens the loadup'on the device. The spiralin'gwf' 'the' lades 0 ahweh;{eliminated"errata; 1 need Train; the :otlir nd' thefeoffat lea sfia distancecorre- Qflbiidifig to the circumferential distance between "succe 'ssivebladesjhas "the additional advantage-of imposing 'a x q s ta ritft tritil ln'rfc nfrn, asjdistinguisiied ifrbmfi'jerky, loadupbmthe'externaldrivirignieans (not"sho'wn)"for isilLiftfS. fHatvuer;where maotifiea1zaie p1aea very ass td gethenfthe blades 15 extend axially of thebutter 'eleinent I3 witliout"ie'ntiering the load upon the driving'nieans'seriously ne -uhirdim. I

"'After the removal of thes t iips" 14," the i'e sidual blades is hi beoiiiid *do'wn' 'to' pfov'ide' a cutting edge at their-"l a ing edges sothat the'resultant cf r o'ss' s'ecjt ion'of chi ade 15 is substantiallyas showniniFig tire 5.

"t t'er' l'e r'n'ent of the character desciib'ed'notbrily 'srvesthepiirfibse ofs'evering the increments of lacquer which have beenex'trudeduh r'ough orifices 12-by'*a heafing action' at the edgesmffs'uch ol ifices, but in addition thereto, by its rotationwitliin' thespace between efiairib er 9 and the interior of'v'es s'el' 1, impartssufficient motion to the supsending liquor in such space as-tol'riimediately suspend 'the severed discrete particles of lacquer, andto maintain thesarne suspended in the suspeiidih tiqubr so that theniiittiirevvhich "is discharged through port 3 is a suspension'oflacquer'particl'es' in thesfispending liquor;it being understood thatacontinuous supply'of suspending liquor is introduced into'tlie"ves"sel"1 thma' a orm. I

From the foregoing. description, those skilled "in the artislio'iild"readily" iide'rstand 'that' the finventioniaccoi'riplish'es itsobjectsarid provides anappa'ratus for the manufacture"of sinailldiscrete"bodies of "uniform size severed from a rnu ltiplicity ofextrusion streams's'o that the rate of production of suchdiscretebo'diesniay be vastl uaereased over 'the 'productionfate possible withapparatus of the character "shown in the" aforesaid "c0- pndiaappneations. Moreover, the nesting "of the exterior cylindrical "wall ofchamber 9' 'within the "cutter e'IeinentIS providesasubstantial"be'aringwhich minimizes vibration and eliminates the warpageand 'rn'isalignment of the cutter blades with reference to the'arrahgenient ofsuch p'artywhereby the'cutter' is maintained stationaryand the chamber is driven" inrotation, and indeed; contemplates thedriving of both at relative speeds of rotation.

While one complete embodiment of the invention has been disclosed indetail, it is to be distinctly understood that the invention issusceptible of numerous modifications, variations, and adaptations whichthose skilled in the arf'wilY be expected" to' make as the apparatus maybe pli'e'dtd'pa murarpreumaa. It is; therefore, to be distinctly'iindefs toodf that the invention is not limited by the foregoingdisclosure eXcept asindi cated in the appenaeduaan. I v

fI-Iavifigi thus: described 'theinvention, what is claimed arid desiredto be secured fby Letters Patent is:

"Adappa'ratus' for ii t'r iiding and slicing lacquer and the likearidsiispendingdhe same in liquor, comprising Mahala-sin vessel'h avinga liquor intake port and a liq or outlet 'pbrt, a chamber "mountedwithin said vessel," said"charnb'er';havirig a 'closed end, an inletend, and" perforated cylindrical wall, 4 means for forcing lacqiler'iiito"'the""chainber through said inlet end and out through "'saidpergforated"cylindrical wall into the 'sp' e"betvveens'aidfiyliiider andsaid vessel, a cutter ha ng an' 'incline'dblade' ridingupori theexterior ofsaid perforated cylindrical wall' within said space, andmeans for -driving said cuter in relative rotation about theaxis'ofsaidcyliridrical wan, said blade being inclined wimf'respeef tothe axis of said cylindricalwall'in the directibnwhich during rotationthereofurges material in said 'space'towa'rdthe outlet pc'rtbr saidvessel.

"nrereaaes'c'itea in'the'file' of this patent UNITED STATES PATENTS

